Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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-SubTopic 10
-Section 55
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Leases - Annual rent (Details) - USD ($) $ in Thousands	Apr. 30, 2019	Jul. 31, 2018	Jul. 15, 2018	Jul. 31, 2017	Jan. 01, 2017
Leases
Annual rent	$ 305	$ 297		$ 289
2020					$ 422
2021					429
2022					$ 437
Research laboratory
Leases
Annual rent			$ 420